The invention relates to fastening devices for affixing tubes, pipes and similar objects to an elongated mounting rail having a C-shaped cross-section transversely of the elongated direction and a elongated space, and a retaining plate. The plate has an internally threaded hole passing through it and running transverse to the plane of the plate, whereby the retaining plate has a width running parallel to the plane of the plate, the width corresponding at most to the width of the elongated space and perpendicular thereto has a length running parallel to the plane of the plate that is greater than the width of the opening.
Fastening devices of the aforedescribed type are utilized particularly in hanging or bracing of objects, such as tubes pipes and similar objects. A mounting rail having a elongated space is fastened to a base or to a structural component, for example, using a plurality of segmental anchors. For fixing a fastening element to the mounting rail a retaining plate is introduced through the elongated space into the internal space of the hollow mounting rail and rotated through an angle, for example 90xc2x0, so that the retaining plate grips around the free ends of the so-called retaining projections. The retaining plate secures the fastening device, for example a threaded pin, with a hole passing through it having an internal thread, the pin engaging at least partially an external section arranged at the fastening device. To provide insertion of the retaining plate into the elongated space the width of the retaining plate corresponds at most to the width of the elongated space and, since the length extending transversely relative to the width of the retaining plate is greater than the width of the space, a gripping of the retaining projections of the mounting rail by the retaining plate is made possible by deviation of the retaining plate inserted into the internal space.
A fastening device comprised of a C-shaped mounting rail and a cornered retaining piece is well-known from the generally known prior art, for example, DE 3811974 C2. The retaining piece is embodied, for example, as a cast piece.
The disadvantage in the generally well-known solution is that the production of the retaining pieces to such dimensions necessarily consumes a relatively large amount of material which is unsuitable if the fastening means is to be economically produced.
Further, the solid construction of the retaining plate negatively affects the overall weight of the fastening device-especially if a plurality of retaining plates are used.
The object of the present invention is to provide a fastening device comprised of a mounting rail and a retaining plate that can be economically produced and is light in weight and, further, provides high stability.
According to the invention, the object is achieved in that the retaining plate on the side facing away from the elongated space, has at least one web that provides for rigidity and positioning.
The retaining plate can be made in a fashion that conserves material and provides for light-weight, so that on the side of the retaining plate facing away from the elongated space of the mounting rail at least one web is arranged, the web providing for rigidity and positioning of the retaining plate. In addition, the web(s) provide(s) also the opportunity of securing the positioning of a fastening device that may be used. In other words, for example, a space extending axially to the internal hole is provided by the web that serves in receiving, in part, the fastening device. Thus, it is possible to use the fastening device without the necessity of cutting to precise length.
Preferably, in order to provide adequate stability of the retaining plate, two webs are provided that run parallel to one another. The webs can each exhibit, depending on the requirements, different cross-sections, such as for example, rounded, rectangular or the like. As regards the dimensions of the webs, the general conditions relevant to the fastening device must be considered.
The webs are advantageously arranged on both sides of the internal thread in order to assure optimum stability especially in the region of the internal thread, since the internal thread produces an attenuation or weakening of the retaining plate.
Preferably, the cross-section of the retaining plate in the region of the webs is designed U-shaped, whereby the free ends form the webs. This embodiment represents the optimum with respect to material consumption and economies.
The webs advantageously form, at least on one side of the internal thread, a reinforcement to prevent overload in the area of the internal thread. For fastening devices whose loading capacity is of primary concern, the webs can be embodied, for example, with a corrugated form over the entire length in order to enhance its stability. In any event, the reinforcement fulfills the function of a flexure point in order to safeguard the mounting rail and consequently the fastening device from overload.
In order to assure economic means for production, the retaining plate preferably has a uniform wall thickness.
Advantageously, the side of the retaining plate facing the elongated space overlaps, at least in the area of the internal thread, the remaining area of the side facing the elongated space, so that on the one hand there is sufficient axial extent of the internal thread and on the other hand the height of the web extending axially to the internal thread is minimized.
The axial extension of the internal thread corresponds advantageously to approximately 1.5 to 4.5 times, preferably 2.25 times, the wall thickness of the retaining plate.
In order to assure economic production of the fastening device, the mounting piece is embodied advantageously as a die-cut and bent piece.